Housing and handle construction for a belt-type sander



Oct. 28, 1969 J. J. BECKERING ET AL 3,474,575

HOUSING AND HANDLE CONSTRUCTION FOR A BELT-TYPE SANDER Filed Jan. 18, 1967 4 Sheets-Sheet I FIG. I H

220 20 197 I47 I48 9 7 I49 J! I53 20' 0 Q I03 189 a 1:1

I94 INVENTORS JACOBUS J- BECKERING ATTORNEY Oct. 28, 1969 J BECKERlNG ET AL 3,474,575

HOUSING AND HANDLE CONSTRUCTION FOR A BELT-TYPE SANDER Filed Jan. 18, 1967 4 Sheets-Sheet 2 INVENIORS JACOBUS J. BECKERING ALLEN G. BEARES X KQ- MM ATTORNEY Oct. 28, 1969 J, BECKERlNG ET AL 3,474,575

HOUSING AND HANDLE CONSTRUCTION FOR A BELT-TYPE SANDER Filed Jan. 18, 1967 4 Sheets-Sheet 3 JACOBUS J BECKERlNG ALLEN G. BEARES Oct. 28, 1969 HOUSING AND Filed Jan. 18, 1967 J. J. BECKERING ETAL 3,474,575 HANDLE CONSTRUCTION FOR A BELT-TYPE SANDER 4 Sheets-Sheet 4 FIG. l2

'5 I ajlJA'b'lYl v.15 r "llllilllllik I O 39 ::r 64 V Z 59 4a FIG. I5 35' 6| m AX. I l 1 l S 2 I l l INVENTORS 39 JACOBUS J. BECKERING ALLEN G. BEARES ATTORNEY United States Patent O 3,474,575 HOUSING AND HANDLE CONSTRUCTION FOR A BELT-TYPE SANDER Jacobus J. Beckering, Bel Air, and Allen G. Bear-es, Towson, Md., assignors to The Black and Decker Manufacturing Company, Towson, Md., a corporation of Maryland Filed Jan. 18, 1967, Ser. No. 610,191 Int. Cl. B24b 23/06 US. Cl. 51-170 21 Claims ABSTRACT OF THE DISCLOSURE This invention relates generally to portable, power driven tools, and particularly to an improved, portable, belttype sanding, polishing or burnishing device and housing and handle construction therefor. More specifically, the disclosure to follow describes a portable, power driven sanding, burnishing or polishing device of the type having a housing and spaced drive and idler pulleys rotatably supported on the housing for rotation about parallel axes.

An electric motor supported upon the housing drives the drive pulley and an endless belt entrained over the drive and idler pulleys. The belt is suitably formed for sanding, burnishing or polishing and the bottom of the housing is open so that the working surface of the belt is exposed at this area. The housing described, as well as a handle detachably secured thereto, are of clam-shell like construction serving to trap various components of the device in place. In addition, the handle, the housing, and a detachable cover provide a passageway through which dust may be removed under the action of a suction fan. A detachable dust bag may be provided to collect the dust.

SUMMARY OF THE INVENTION An important object of the present invention is to provide an improved housing construction for portable sanding, polishing and burnishing devices and the like which housing is split or divided longitudinally in a fashion such that assembled it locates, traps and supports operating parts of the device in place in a relatively simple and efiicient manner.

Another important object of the present invention is to provide an improved housing construction of the above character which locates and supports the drive motor together with drive and idler pulley means in a compact and elficient arrangement.

Another important object of the present invention is to provide an improved housing construction of the above character which electrically isolates the drive motor and yet permits easy access thereto for service and/or repair.

Still another important object of the present invention is to provide an improved housing construction of the above character which itself includes a minimum of separate parts and further minimizes the number of additional supports and fasteners required for component parts of the device.

Still another important object of the present invention is to provide an improved housing construction of the above character together with an improved handle construction wherein the handle construction also is split or divided longitudinally such that assembled, the handle locates, traps and supports the device electrical control components in place.

Still another important object of the present invention is to provide an improved housing and handle construction of the above character wherein the handle is secured to the housing in a simple, subtle and secure fashion, and wherein together, the housing and handle present an over all compact and aesthetically pleasing appearance.

Further objects include the provision of an improved portable device and housing and handle construction therefor of the character described which is relatively inexpensive to manufacture, rugged and light-weight in construction, and safe and reliable in use.

Other objects and advantages of the present invention will become more apparent from a consideration of the following detailed description taken in conjunction with the drawings in which:

DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view of a portable sanding device embodying the present invention;

FIG. 2 is a sectional View of FIG. 1 taken along the line 22 thereof;

FIG. 3 is a sectional view of FIG. 2 taken along the line 33 thereof;

FIG. 4 is an exploded, perspective view illustrating the clam shell housing and handle construction of the present invention, shown with the internal parts removed for clarity;

FIG. 5 is a sectional view of FIG. 1 taken along the line 5--5 thereof;

FIG. 6 is a fragmentary elevational View of the other side of the device as shown in FIG. 1, and seen with the gear cover removed;

FIG. 7 is a sectional view of FIG. 6 taken along the line 77 thereof;

FIG. 8 is a sectional view of FIG. 6 taken along the line 88 thereof;

FIG. 9 is a sectional view of FIG. 1 taken along the line 9-9 thereof;

FIG. 10 is a side elevational view illustrating a preferred form of gear cover which is employed with the dust collection construction;

FIG. 11 is a View similar to FIG. 10 illustrating a modified form of gear cover which is employed without the dust collection construction;

FIG. 12 is a plan view of the upper housing frame member shown in FIG. 4 and looking in the direction of the arrows 1212 thereof;

FIG. 13 is an enlarged, sectional view of the structure of FIG. 1 taken along the line 13-13 thereof;

FIG. 14 is an enlarged plan view of the motor housing cover shown in FIG. 4 and looking in the direction of the arrows 14-14 thereof; and

FIG. 15 is a sectional view of the structure of FIG. 13 taken along the line 15--15 thereof.

BROAD STATEMENT OF THE INVENTION Broadly described, the present invention relates to a portable sanding, polishing or burnishing device of the type having a drive motor, drive and idler pulley means, and an endless belt having spaced upper and lower runs and entrained over said pulley means; that improvement which comprises a split, elongated housing including upper and lower frames detachably secured along a longi tudinally extending parting plane and which together define a top, a side wall, and a motor housing extending inwardly from said side wall and beneath and spaced from said top, said motor being supported by said motor housing between said belt runs and including a motor shaft, first bearing means rotatably supporting said motor shaft and being trapped within first recess means formed at said parting plane, pulley shaft means rotatable with said drive pulley means and being in driven relation with said motor shaft, second bearing means trapped within second recess means at said parting plane and rotatably supporting said pulley shaft means, handle means for control and manipulating of said device including an elongated portion overlaying a major portion of said housing top and secured thereto and an upwardly facing ledge adapted to seat beneath a downwardly facing ledge on said housing, said handle means includes detachable handle and handle cover portions secured together along a longitudinal parting plane substantially normal to said first mentioned parting plane, a handle grip formed by said handle and handle cover portions, switch means for controlling said motor, said switch means being trapped between said handle and handle cover portions at said handle grip.

DETAILED DESCRIPTION Referring now more specifically to the drawings, a compact belt sander embodying the present invention is illustrated generally at 11 in FIGS. 1-3 and is seen to include a housing 13 having a handle assembly 15 secured thereto. A drive motor 17 is positioned within the housing 13 and is adapted to be connected to a power source through a line cord 19 and is controlled by a trigger switch 21. The motor 17 is drivingly interconnected to a drive pulley 23 positioned within the housing 13 and preferably to the rear of the motor. An idler pulley 25 is also positioned within the housing 13 and is disposed forwardly of the motor 17. An endless belt 27, suitably formed for abrading, polishing or burnishing, is entrained over the pulleys 23, 25 and has upper and lower runs 27A, 27B above and below the motor 17. The belt 27 moves with rotation of the drive pulley 23, the latter having a friction sleeve 23 thereon, and turns the idler pulley 25. The bottom of the housing 13 is substantially completely open so that the belt lower run 27B is exposed, the latter being backed by a smooth shoe plate 26. Thus, when the motor 17 is energized, the pulley 23 turns and by friction causes the belt 27 to move and the pulley 25 to turn whereupon the device is ready for use.

According to one feature of the present invention, the housing 13 is constructed so as to support and retain in a novel manner the drive motor 17 together with the drive and idler pulleys 23, 25. In another feature, the handle 15 of the present invention is constructed to trap the control switch 21 and the line cord 19 in place and cooperates with and is secured to the housing 13 in a manner calculated to provide a compact, light-weight, and well balanced device as well as one which presents an overall aesthetically pleasing appearance.

Turning now to FIGS. l-4 and l214, the housing 13 is seen to include detachably secured, mating, upper and lower frame members 29, 31 which preferably, but not necessarily, are constructed of cast aluminum. The upper frame member 29 has an elongated top 32 and side wall portion 33 while the lower frame member 31 has an elongated side wall portion 34 which is substantially coextensive with and mates with the side wall portion 33. A motor housing 36 comprising a mating pair of substantially semicylindrical motor housing portions 37, 39 are rigid with and extend inwardly from the side wall portions 33, 34, respectively. The motor housing portions 37, 39 preferably are constructed integral with the frame members 29, 31, respectively, and are disposed to closely interfit when the side wall portions 33, 34 are juxtaposed. A separate motor housing cover forms substantially a continuation of the motor housing portion 37 and mates with the inner end of the motor housing portion 39 for a purpose hereinafter set forth. Screws 4t], 41 extend through bosses 36, 38 in the side wall portion 33 and motor housing portion 37 and are threaded into openings 44, 46 in the side wall portion 34 and motor housing portion 39, respectively, to secure the frame members together. The cover 35 is secured in place on the motor housing portion 39 by screws 42 which extend through the former and are threaded into openings 48 in the latter.

The motor 17 shown is a conventional universal type and is disposed substantially completely within the motor housing 36 and has an armature shaft 43 supported fore and aft by spherical sleeve or needle bearings 45, 47 trapped in recesses 49, 51 which are shaped complementary to the bearings 45, 47 and are formed at the parting plane between the frame member side wall portions 33, 34 and between the motor housing portion 39 and the cover 35, respectively. Of course, if straight type bearings are employed, the recesses 49, 51 would be correspondingly straight in configuration.

An armature windings assembly 53 is fitted to the shaft 43 and is rotatable within a field windings subassembly 55, the latter being fixed within the motor housing members 37, 39. A commutator 57 is fixed to the shaft 43 for rotation therewith and is located between the armature windings assembly 53 and the bearing 47. A pair of electrical brushes 59, 61 are engageable with the commutator 47 and are supported in brush holders 63, 65, respectively.

As shown in FIG. 13, at least one and preferabl both the motor housing portion 39 and the motor housing cover 35 are formed with recess means 64, 66 at the parting plane therebetween which receive and trap the brush holders 63, 65 in place. In this manner, the brush holders 63, 65 can be removed and the brushes 59, 61 replaced simply by removing the motor housing cover 35 and does not require disassembly of any of the other housing components. A fan 73, which serves both to draw cooling air past the motor 53 and to assist in dust collection during use of the device, is pressed on the armature shaft 43 adjacent the bearing 45 and rotates freely in a substantially cylindrical cavity 68 formed in the motor housing portions 37, 39.

To energize the motor 17, the brushes 59, 61, which are biased against the commutator 57, are connected to a pair of leads 56, 58, the former being a power lead from the line cord 19 and the latter being connected to the motor field. Another lead 60 interconnects the field and the trigger switch 21 which in turn is connected to another power lead 62 carried by the line cord 19 so that when the line cord is plugged into an electrical source and the switch 21 closed, the motor 17 is energized and the armature shaft 43 rotated in the usual manner.

The other end of the armature shaft 43 extends beyond the bearing 45 and outside the housing 13, as shown in FIG. 2, and is formed with pinion teeth '75, or alternatively, has a pinion fixed thereto. An idler gear 77 is rotatably supported on a stub shaft 81 pressed into the side wall portion 34 and is engaged by the pinion teeth 75 so as to be driven thereby. A retainer 83 holds the idler gear 77 in place on the shaft 81. The idler gear 77 also engages an intermediate gear 85 held in place by a retainer 87 on a stub shaft 89 also pressed into the housing member 31. An intermediate pinion 93 is formed on a hub of the gear 85 or is keyed thereto so as to rotate therewith and drivingly engages a spindle gear 95 which is keyed to a pulley shaft 97 and held in place thereon by a screw 99 and a lock washer 101. The pulley shaft 97 extends substantially parallel to the armature shaft 43 and through a mating pair of generally semicylindrical shaft supports 111, 113 depending inwardly from the side wall portions 33, 34, respectively, and preferably integral therewith. A pair of sleeve or needle bearings 103, are trapped in axiaily spaced, cylindrical recesses 107, 109 formed at the parting plane between the shaft supports 111, 113 and r0- tatably support the pulley shaft 97. A plurality of screws 115 detachably secure the supports 111, 113 and assist in holding the frame members 29, 31 together.

The drive pulley 23 is provided with a substantially central opening therethrough 117 which receives the shaft 97 in press fit relation so that the pulley 23 turns with rotation of the shaft 97. The drive pulley 23 is disposed closely adjacent the rearward end of the motor housing 36 while the idler pulley 25 is disposed closely adjacent the forward end of the motor housing. The idler pulley 25 is rotatably supported by sleeve or needle bearings 119, 121 upon a shaft 123 carried by a generally U-shaped pulley bracket 125. The shaft 123 is formed with splines 127 which interferingly engage the bracket 125 to prevent shaft rotation. The pulley bracket 125 is supported upon a support bracket 129 for pivotal and longitudinal movement relative thereto by a pivot pin 131 pressed into openings in reawardly extending legs 133, 135 on the pulley bracket 125 and extending freely through longitudinal slots (not shown) in arms 141, 143 forming a part of the support bracket 129. The idler pulley 25 is normally held in the position shown in FIGS. 2 and 3 by a torsion spring 145 entrained around the pin 131 and having spring lugs engaging the bracket 125 so that belt 27 entrained over the drive pulleys 23, 25 is tensioned. However, to remove and/or replace the belt 17, the idler pulley 25 is moved toward the drive pulley by manipulating a lever device 147 which is pivoted on the side wall portion 34 and operably connected to the pulley bracket 125 and adapted to move it and the ider pulley 25 carried thereby rearwardly or toward the left against the force of the spring 145 (FIG. 2). This lever device 147 forms no part of the present invention but is illustrated and described in detail in the copending application of Jacobus J. Beckering and Lewis H. Rohr, Ser. No. 580,367, filed Sept. 19, 1966, now Patent No. 3,393,573, granted July 23, 1968, and owned by the assignee of the present application, so that reference may be made thereto for a better understanding thereof.

In addition, the idler pulley 25 is adjustable in a plane transverse to the direction of belt movement by manipulating a tracking device 149. This device includes a knob 148 threaded on the end of the shaft 123 and adapted to move the shaft axially and pivot the bracket 125 about the pin 131 to maintain the center of pressure on the pulley 25 aligned with the center of resistance on the belt 17. Again, this device 149 forms no part of the present invention but for a better understanding thereof, reference may be made to the copending application of Jacobus J. Beckering, Ser. No. 590,026, filed Oct. 27, 1966, and owned by the assignee of the present application.

As described above, the housing 13 is formed of at least two parts, i.e., frame members 29, 31, adapted to mate along substantially a longitudinal, horizontal plane which intersects the armature shaft bearings 45, 47 and the pulley shaft bearings 103. Thus, the frame members 29, 31 form a clamshell-like construction Which, when open, permits easy removal and/or replacement of any of the motor and drive pulley components and, when closed, secures these parts in place in a simple but highly effective manner without requiring special fasteners and/or supports for any of these components. In addition, this clamshell-like configuration eliminates the need for expensive machining techniques and therefore contributes greatly to an overall reduction in cost of the device. The use of the separate motor housing cover 35 maintains the basic clamshell arrangement and, in addition, permits easy removal and/or replacement of the motor brushes 59, 61 while leaving the rest of the housing 13 intact.

Along with the motor 17 and the components of the drive pulley 23, the clamshell housing 13 traps the belt tensioning and tracking operating mechanisms 147, 149 in place therebetween in a simple, facile manner which again requires no special fasteners or supports. Furthermore, the brackets 125, 129 which provide support for the idler pulley 125, as well as to facilitate both tensioning and tracking movement thereof, are in turn supported directly on the frame member 31 so as to be easily removable if desired when servicing the motor 17 and the drive pulley components.

Of substantial importance in the construction thus far described is the location of the motor housing 36 and the motor 17 between the belt runs 27A, 27B, and the particular disposition of the motor 17 together with the arrangement of the transmission connecting the motor 17 and the drive pulley 23. Thus, by locating the motor 17 between the pulleys 23, 25 and the belt runs 27A, 27B, the device 11 is made more compact and its center of gravity lowered somewhat making it considerably easier to handle. Furthermore, as shown, the motor axis is disposed transverse to the belt runs 27A, 27B, and generally parallel to the axes of the pulleys 23, 25. This, together with the disposition of the gear transmission outside the housing 13 greatly decreases the space between the pulleys 23, 25 required by the motor 17 as compared with one where the motor axis is disposed along the belt runs and the transmission located within the housing. Thus, a relatively large, more powerful motor can be employed without significantly increasing the size of the device thereby facilitiating a highly efficient, easily handled tool.

In accordance with another feature of the present invention, the frame member top 32 has a relatively large slot or opening 151 formed therein overlaying the motor housing 36 and the pulley shaftsupports 111, 113. This opening 151 advantageously exposes all of the screws 41, for easy access in assembling and disassembling the housing 13, and in addition, contributes materially to reducing both the overall weight and cost of the device 11. In assembly, the opening 151 is covered by a forward portion of the handle assembly 15, to be described in detail below, which advantageously extends to a forward region of the housing 13. The handle assembly 15 is constructed of a considerably lighter weight material than the housing 13 so that a considerable weight savings is achieved.

Turning now to FIGS. 1, 3 and 4, the handle assembly 15 is seen to include handle and handle cover portions 153, 155 detachably secured by screws 156 along a longitudinal, vertical plane. Like the housing 13, the handle assembly 15 forms essentially a clamshell-like construction and traps the trigger switch 21 and the line cord 19 in place therebetween.

As shown in FIGS. 3 and 4, the handle and handle cover 153, 155 are formed with mating rear handle grip portions 152, 154, respectively. The trigger switch 21 is trapped between the grip portions 152, 154 and includes an apertured mounting plate 158 adapted to fit on a pair of posts 160 formed in the handle grip portion 152 and held in place thereon by a tubular boss 162 formed on the handle grip portion 154. A trigger 164 is pivoted on the mounting plate 158 and extends through an aperture 166 in the handle grip portions 152, 154 for easy access by the operator during use of the device. The line cord 19 extends through an aperture 168 formed at the juncture between the handle and handle lever 153, 155 and has a protective sheath 170 encased therearound and provided with a flange 172 adapted to snugly fit in a recess 174 also at the handle and handle cover juncture. In addition, the handle and handle cover 153, 155 may be formed with portions 140, 142, respectively, removed to receive a two-speed switch (not shown). Advantageously, the handle and handle cover 153, 155 with or without the portions 141), 142 removed, can be molded using the same basic dies, for example by employing removable die pins as is customary in the art.

The handle and handle cover 153, 155 partially embrace the housing 13 and are secured thereto in a novel, simple and effective manner calculated to provide both utility as well as simplicity of design. Thus, the handle and handle cover 153, 155 have forwardly projecting, upwardly facing ledges 167, 169 adapted to seat beneath downwardly facing ledges 171, 179 formed on dependent, slotted ears 180, 182 at the rearward end of the frame top 32. The forward portions of the handle and handle cover 153, 155 are adapted to receive an upwardly projecting lug 177, integral with the frame top 32, therebetween. A mounting screw 175 extends through an opening in the handle cover 155 and an opening in the lug 177 and is threaded into an opening in the handle 153 (see FIG. 5 In addition, a mounting bolt 173 extends through bosses 176, 178 in the handle and handle cover 153, 155, respectively, and through the slotted ears 180, 182 and is threaded into a nut 184 trapped in the boss 176. The screw 175 and the bolt 178 of course supplement the screws 156 in holding the handle 153 and handle cover 155 together; however, it will be apparent that when it is desired to remove the handle assembly 15 before dismantling the housing 13 for service or replacement of the motor or drive pulley assembly, only the screw 175 and the bolt 173 are removed whereupon the handle assembly 15 is detachable from the housing 13 but is still intact. In addition to the rear handle portions 152, 154, the handle and handle cover 153, 155 are provided with mating front handle portions 163, 165 which, together with the former, facilitate easy two-handed operation and control of the device 11.

Turning now to FIG. 2, the fan 73 is seen to include oppositely disposed sets of blades 183, 185 separated by a generally disc shaped bafiie 181, the baffle being disposed closely adjacent the wall of the cylindrical cavity 68 so as to effectively divide the latter into two chambers. The blades 183 serve to draw cooling air axially past the motor 17 and to this end, the inner radial wall of the cavity 68 has a relatively large aperture 189 surrounding the armature shaft 43. This cooling air is then exited through arcuately spaced openings 187 formed in the peripheral wall of the cavity 68-. The fan blades 185 serve to draw dust from the workpiece and delivers it to a dust bag when the dust collecting construction is active and are correspondingly inactive when the dust collection construction is inactive.

During rotation of the fan 73, the blades 185 draw air through openings 190 formed in the outer radial wall of the cavity 68 (see FIGS. 4 and 6). A gear cover 191 is fixed to the housing 13 by screws (not shown) adapted to extend through aligned bosses 193, 194 in the cover 191 and the side walls 33, 34, respectively. The cover 191 has an outer substantially peripheral lip 195 which seats snugly in a recess 197 formed in the frame member side walls 33, 34. A continuous inner lip 199 formed on the gear cover 191 seats tightly on a continuous lip 201 formed on the frame member side walls 33, 34 and circumscribing the transmission gears 75, 77, 85, 93, 95 so as to seal E these gears when the cover 191 is in place. In addition, the engaged lips 199, 201 and lip and recess 195, 197 define a dust passage 202 therebetween. which communicates with the suction openings 190 and through which dust is adapted to be transported.

Dust is removed from the work during use of the device through an intake slot 203 located in the bottom of the handle and handle cover 153, 155 beneath the ledges 167, 169 and adjacent the rear end of the lower belt run 27B. The intake slot 203 communicates with an inlet pocket 205 in the gear cover 191 which, in the embodiment shown in FIGS. l-lO, is open to the dust passage 202. The suction generated by the fan blades 185 is communicated to the passage 202 and the intake slot 203 so that during use of the device, dust is drawn into the intake slot 203 and inlet pocket 205, through the passage 202 and into the fan blades 185 through the openings 190.

The dust drawn into the fan blades 185 is thrown radially outwardly by centrifugal force through an outlet passage 207 formed in the peripheral wall of the cylindrical cavity 68 (FIG. 7). The gear cover 191 has an integral outlet tube 209 communicating with the out let passage 207. A dust bag assembly 210 including a dust bag 215 is provided with an exhaust tube 211 communicated with the bag 215 and adapted to be inserted in the outlet tube 209 and retained therein by a clip spring 213. Thus, the dust blown by the fan blades 185 through the outlet passage 207 is also blown through the outlet tube 209 and exhaust tube 211 and into the bag 215. The bag assembly 210 is removable simply by pulling on the exhaust tube 211 with a force suflicient to release the spring 213 from the outlet tube 209.

If it is desired to use the device 11 without the dust collecting device, a modified gear cover shown generally at 219 (FIG. 11) is substituted for the gear cover 191. The modified gear cover 219 is identical to that shown at 191 with the exception that the modified cover 219 is provided with a wall 221 across the top of the inlet pocket 205 and which is adapted to seat tightly against an outer horizontal edge 220 of the ledge 167 on the handle 153. The cooperating wall 221 and edge 220 seal the inlet pocket 205 and therefore the intake slot 203 from the dust passage 202 and the suction effect of the fan blades so that no dust is picked up when the modified cover 219 is used. In addition, the outlet tube 209 on the modified cover 210 is sealed off by an integral wall 223.

It will be appreciated that when it is desired to convert from active to inactive dust collection, or vice-versa, all that is necessary is to interchange the covers 191, 219 and add or remove the dust bag assembly 210 as is the case. This construction is advantageous not only from the viewpoint of providing a relatively easy and inexpensive change over from active to inactive collection, but also for the more important reason that the gear covers 191, 219 can be formed using basically the same die. Thus, removable inserts are used in the die to alternatively from the wall 121 and the outlet tube wall 223 so that in this way, manufacturing costs are kept to a. minimum.

By the foregoing, there has been disclosed an improved housing and handle construction for portable sanding devices and the like calculated to fulfill the inventive objects hereinabove set forth, and while a preferred embodiment of the present invention has been illustrated and described in detail, various additions, substitutions, modifications and omissions may be made thereto without departing from the spirit of the invention as encompassed by the appended claims.

We claim:

1. In a portable sanding, polishing or burnishing device of the type having a drive motor, drive and idler pulley means, and an endless belt having spaced upper and lower runs and entrained over said pulley means; that improvement which comprises a split, elongated housing including upper and lower frames detachably secured along a longitudinally extending parting plane and which together define a top, a side wall, and a motor housing extending inwardly from said side wall and beneath and spaced from said top, said motor being supported by said motor housing between said belt runs and including a motor shaft, first bearing means rotatably supporting said motor shaft and being trapped within first recess means formed at said parting plane, pulley shaft means rotatable with said drive pulley means and being in driven relation with said motor shaft, second bearing means trapped within second recess means at said parting plane and rotatably supporting said pulley shaft means, handle means for control and manipulation of said device including an elongated portion overlaying a major portion of said housing top and secured thereto and an upwardly facing ledge adapted to seat beneath a downwardly facing ledge on said housing, said handle means includes detachable handle and handle cover portions secured together along a longitudinal parting plane substantially normal to said first mentioned parting plane, a handle grip formed by said handle and handle cover portions, switch means for controlling said motor, said switch means being trapped between said handle and handle cover portions at said handle grip.

2. A construction as defined in claim 1 wherein said motor shaft and said pulley shaft are generally parallel and extend transversely to said belt runs.

3. A construction as defined in claim 1 wherein said first bearing means includes a pair of bearings rotatably supporting said motor shaft at axially spaced locations therealong, said first recess means including aligned recesses arranged transversely of said belt runs.

4. A construction as defined in claim 1 wherei said frame means together define an elongated belt and pulley housing having a top and a side wall, a motor housing extending inwardly from said side wall and spaced beneath said housing top, said motor housing being positioned between said belt runs and receiving and supporting said motor.

5. A construction as defined in claim 4 wherein said motor and pulley shafts extend transversely to said belt runs and through said side wall, and gear means outside said side wall interconnecting said shafts.

6. A construction as defined in claim 1 wherein said frame means includes a pair of elongated frame members having cooperable side wall portions and generally concave motor housing portions, a commutator on said motor shaft and within said motor housing portions, brush holder means adjacent said commutator and seated in recess means in one of said motor housing portions, the other of said motor housing portions being cooperable with said one motor housing portion to trap said brush holder means in said recess means.

7. A construction as defined in claim 6 wherein said side wall and motor housing portion of each said frame member are integrally formed, said other motor housing having a separate cover plate which cooperates with said one motor housing portion to trap said brush holder means in place within said motor housing.

8. A construction as defined in claim 1 wherein said frame means include upper and lower members having cooperable side wall potrions and generally concave motor housing portions extending inwardly from said side wall portions, said motor including a stationary field trapped between said motor housing portions.

9. A construction as defined in claim 8 wherein said first recess means includes a pair of aligned recesses, one of which is formed at the side wall portions and the other being formed at said motor housing portions.

10. A construction as defined in claim 1 wherein said frame means includes upper and lower members having cooperable motor housing portions which support said motor, said drive and idler pulley means being supported at spaced locations by said frame members with said motor housing portions intermediate thereof.

11. A construction as defined in claim 10 wherein said drive and idler pulley means includes a drive pulley and an idler pulley supported upon a drive pulley shaft and an idler pulley shaft, respectively, said drive pulley shaft being trapped and rotatably supported between said frame members, said idler pulley shaft being supported by said frame members for limited movement relative to said drive pulley shaft.

12. A construction as defined in claim 11 wherein said idler pulley shaft is carried by bracket means, said bracket means being supported upon said frame members for pivotal movement about an axis generally normal to said drive and idler pulley shafts, and for movement of said idler pulley shaft toward and away from said drive pulley shaft.

13. A construction as defined in claim 12 wherein said idler pulley shaft is nonrotatably carried by said bracket means, and means trapped between said frame members for pivoting said bracket means.

14. A construction as defined in claim 12 which includes manually operable means supported on said frame members and engageable with said bracket means to move said idler pulley shaft toward and away from said drive pulley shaft, said manually operable means being accessible from outside said frame members.

15. A construction as defined in claim 11 which includes manually operable means for moving said idler pulley shaft relative to said drive pulley shaft, said manually operable means being accessible from outside said frame members.

16. A construction as defined in claim 1 wherein said housing top is provided with an upwardly extending lug, said handle having a recess adapted to receive said lug when said ledges are in seating relation, and screw means adapted to interconnect said handle and said lug.

17. A construction as defined in claim 1 wherein said motor housing includes upper and lower, generally concave portions rigid with said upper and lower frames, respectively, fastener means interconnecting said motor housing upper and lower portions, said housing top having a slot above said motor housing to reduce the weight of the device and permit easy access to said fastener means, said handle elongated portion overlaying said slot in said housing top.

18. A construction as defined in claim 1 wherein said upper and lower housing portions have cooperable upper and lower shaft supports, respectively, rigid therewith and extending inwardly from said side wall, said drive pulley being supported upon a shaft trapped between said shaft supports, fastener means interconnecting said shaft supports, said housing top being slotted above said bosses to reduce the weight of the device and permit easy access to said fastener means.

19. A construction as defined in claim 1 wherein said motor housing includes cooperating upper and lower portions integral with said upper and lower frame portions.

20. A construction as defined in claim 1 wherein said housing top is provided with a relatively large aperture substantially above said motor housing, said handle elongated portion overlaying and covering said aperture.

21. A construction as defined in claim 20 wherein said housing top has an upwardly projecting lug integral therewith and located forwardly of said aperture, said handle having a recess therein adapted to receive said lug when said handle and housing ledges are in engagement, and screw means interconnecting said handle and said lug.

References Cited UNITED STATES PATENTS 3,180,063 4/1965 Burrows et a1 51170.4 3,176,436 4/1965 Anton 51l70.4 3,391,499 7/1968 Batson 51-170.4 3,049,842 8/1962 Murschel 51-273 X 2,965,774 12/1960 Rangus 310-50 3,362,111 1/1968 Foell et al. 5117O 3,359,689 12/1967 McCarty et al. 51170 JAMES L. JONES, JR., Primary 'Examiner 

